Democratic Partisan Gerrymanders, 1972-present

August 23rd, 2017, 12:39am by Sam Wang

The Princeton Gerrymandering Project makes it easy to browse all gerrymandering offenses for a given year. We are now starting to cross-reference these offenses with who had control over the redistricting process. It’s a daunting task, but our statistical analyst Brian Remlinger is on the case.

Below is a list of states from the 1970s through the 1990s that failed at least two of our three statistical tests of gerrymandering in at least one election. There are 14 of them. Of these, only three gave the advantage to the party that controlled the districting process. These are indicated in red. They are all Democratic gerrymanders.

1970s:

Illinois looks like a Republican gerrymander in 1972 and 1974. However, it was redistricted by a bipartisan state government.

Ohio* looks like a Republican gerrymander in 1972 and 1974. However, it was redistricted by a Democratic state government.

Kentucky looks like a Democratic gerrymander in 1972 and was redistricted by a Democratic statehouse.

Michigan looks like a Republican gerrymander in 1976 but was redistricted by a bipartisan statehouse.

Alabama looks like a Republican gerrymander in 1978 but was redistricted by a Democratic statehouse.

Illinois looks like a Republican gerrymander in 1982 but was redistricted by a court.

Ohio looks like a Republican gerrymander in 1982 but was redistricted by a bipartisan statehouse.

New York looks like a Republican gerrymander in 1982 but was redistricted by a bipartisan statehouse after preclearance was denied by the Justice Department for an initial bipartisan map.

Louisiana looks like a Republican gerrymander in 1986, but we ignored it because the jungle primary system distorts election results.

1990s:

California looks like a Republican gerrymander in 1992 and 1998, but was redistricted by a court.

Texas looks like a Democratic gerrymander in 1992 and 1994 and was (mostly) drawn by Democrats. The map was court-modified in 1996 (the famous Bush v. Vera case).

New York looks like a Republican gerrymander in 1998, but was redistricted by a court.

Illinois looks like a Republican gerrymander in 2000, but was redistricted by a court.

At that point, partisan gerrymandering starts to erupt – with Republicans as the most common offenders. Certainly there are exceptions – Maryland being one, where Democrats drew one Republican Congressional district out of existence, the subject of the current case of Benisek v. Mack. But in the 2000s and the 2010s, the tests flag a clear pattern:

2000s:

Michigan looks like a Republican gerrymander in 2002, 2004, and 2006 and was redistricted by a Republican statehouse.

Ohio looks like a Republican gerrymander in 2004 and 2006 and was redistricted and was redistricted by a Republican statehouse.

Pennsylvania looks like a Republican gerrymander in 2004 and was redistricted by a Republican statehouse.

Florida looks like a Republican gerrymander in 2006 and 2008 and was redistricted by a Republican statehouse.

North Carolina looks like a Democratic gerrymander in 2010 and was redistricted by Democrats.

California looks like a Republican gerrymander in 2008 but was redistricted by Democrats.

Illinois looks like a Republican gerrymander in 2002, 2006, 2008, and 2010 but was redistricted by a bipartisan statehouse.

2010s:

Pennsylvania looks like a Republican gerrymander in 2012, 2014, and 2016 and was redistricted by a Republican statehouse.

Michigan looks like a Republican gerrymander in 2012, 2014, and 2016 and was redistricted by a Republican statehouse.

North Carolina looks like a Republican gerrymander in 2012, 2014, and 2016 and was redistricted by a Republican statehouse.

Wisconsin looks like a Republican gerrymander in 2016 and was redistricted by a Republican statehouse.

Ohio looks like a Republican gerrymander in 2012 and was redistricted by a Republican statehouse.

Virginia looks like a Republican gerrymander in 2012 and was redistricted by a Republican statehouse (a court redrew the state’s Congressional lines in 2016).

Texas looks like a Republican gerrymander in 2016 and was redistricted by a Republican statehouse, later modified by the courts.

New Jersey looks like a Republican gerrymander in 2012. It was redistricted by a bipartisan political committee.

Note in particular that now the offenses are repeated from election to election, which indicates a more durable set of gerrymanders.

I do not think that Democrats are particularly noble when it comes to partisan gerrymandering. A more plausible hypothesis is that the stars aligned for Republicans: means (redistricting technology), motive (the widening gulf between the parties), and opportunity (the wave election of 2010). We’re currently preparing an article on the subject.

In the meantime, I welcome comments and corrections.

*Interestingly, it has been claimed that Ohio in the 1970s was an effective Democratic gerrymander. For now I will simply say that in terms of partisan representation, that appears not to be the case. There are other ways to label gerrymandering, and we are thinking about where this discrepancy in interpretations comes from.

4 Comments so far ↓

Very interesting, congratulations Brian! So why would Democrats gerrymander a Republican district?

Other than sheer incompetence, which is always a possibility, a couple of thoughts:

1) It’s a transitional period. 70’s were a time of white flight to the inner-ring suburbs and eventually exurbs. If you are using stale data to gerrymander, you lose.

2) Intra-party score settling. As Sam said in a previous thread, Democrats couldn’t conceive of losing the House, so gerrymandering a seat away from a troublesome committee member to give it to a powerless Republican might be SOP.

I don’t know if I would call it incompetence but it was certainly more difficult to gerrymander back then. Aside from lacking the sophisticated redistricting algorithms available today, voters were much more willing to change their minds. Take for example, these histograms of the within cycle variance of the two party vote shares for each district from 1972-present. It’s really pretty extraordinary how stable preferences have become over time!

I’m just guessing, but maybe a desire to create majority-minority districts for purposes of minority representation? That could give them a representative voice at the expense of their reliably Democratic votes in other districts.